#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int exchange(int* x, int* y)
{
	int t = *x;
	*x = *y;
	*y = t;
	return 0;
}
int main()
{
	int a = 0, b = 0;
	printf("please enter two num :");
	scanf("%d %d", &a, &b);
	exchange(&a, &b);
	printf("%d %d", a, b);
}